JPS60244942A - Automatic exposure adjusting device - Google Patents

Automatic exposure adjusting device

Info

Publication number
JPS60244942A
JPS60244942A JP59103192A JP10319284A JPS60244942A JP S60244942 A JPS60244942 A JP S60244942A JP 59103192 A JP59103192 A JP 59103192A JP 10319284 A JP10319284 A JP 10319284A JP S60244942 A JPS60244942 A JP S60244942A
Authority
JP
Japan
Prior art keywords
light
light source
sensor
slit
linear part
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP59103192A
Other languages
Japanese (ja)
Other versions
JPH0452932B2 (en
Inventor
Yasuhiro Takai
高井　康博
Kenichi Morimoto
賢一 森元
Seiichi Yoshida
吉田　成一
Kosei Tagawa
孝生 田川
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sharp Corp
Original Assignee
Sharp Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sharp Corp filed Critical Sharp Corp
Priority to JP59103192A priority Critical patent/JPS60244942A/en
Priority to US06/734,097 priority patent/US4636063A/en
Priority to DE19853517915 priority patent/DE3517915A1/en
Publication of JPS60244942A publication Critical patent/JPS60244942A/en
Publication of JPH0452932B2 publication Critical patent/JPH0452932B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/50—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control
    • G03G15/5025—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control by measuring the original characteristics, e.g. contrast, density
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/32—Projection printing apparatus, e.g. enlarger, copying camera
    • G03B27/52—Details
    • G03B27/54—Lamp housings; Illuminating means
    • G03B27/542—Lamp housings; Illuminating means for copying cameras, reflex exposure lighting
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Control Of Exposure In Printing And Copying (AREA)
  • Exposure Or Original Feeding In Electrophotography (AREA)

Abstract

PURPOSE:To facilitate the control over the quantity of light of a light source during conducting variable power by installing the photodetection sensor of a copying machine which varies in copy magnification continuously under the light source closely, and arranging a light shield plate which has a slit in an optical path of exposure near an original surface. CONSTITUTION:Light emitted by the light source is reflected by a reflecting plate 2 and converged on a linear part 3a almost perpendicular to the figure surface. Its reflected light beam l is passed through mirrors 8, 9, 10, and 12 and focus-adjusted by a lens 11 to form its image on a photosensitive drum 13, which is thus exposed. The light shield plate 7 which has the slit 7a of about 5-7mm. on the optical path is provided between 3a on an original and the reflecting mirror 8. The photodetection sensor 5 is provided under the reflecting plate 2 and an L-shaped light shield plate 6 with an opening part 6a is provided between the photodetection sensor 5 and reflecting plate 2. The sensor 5 receives reflected light from a linear part 3b which is set distance (x) ahead of the linear part 3a and sets the time for the feedback control of a control circuit which is not shown in a figure. The sensor 5 photodetects the light under the same conditions even during magnification varying operation. Consequently, the light source is controlled without any complicate arithmetic during conducting variable power.

Description

【発明の詳細な説明】 く技術分野〉 この発明は可変倍率の複写機の自動露光調整装置に関す
る。DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an automatic exposure adjustment device for a variable magnification copying machine.

〈従来技術とその欠点〉 従来、可変倍率の複写機で自動露光調整を行う場合、倍
率を変化させると、同じ原稿面からの受光センサの検出
値と感光体の露光量の関係も変化を来す。そのため前記
検出値を複雑な演算処理回路でその倍率に対応する数値
に処理し、その数値に基いて光源の光量を制御していた
。そのため回路構成が複雑になり、装置の保守に手間が
かかると言う欠点があった。また倍率の変化と前記受光
センサの検出値と感光体の露光量との関係の変化が一定
でないため正確な演算処理の設定が非常に困難であると
いう不都合があった。<Prior art and its drawbacks> Conventionally, when automatic exposure adjustment is performed on a variable magnification copying machine, when the magnification is changed, the relationship between the detection value of the light receiving sensor from the same document surface and the exposure amount of the photoreceptor also changes. vinegar. Therefore, the detected value is processed into a numerical value corresponding to the magnification using a complicated arithmetic processing circuit, and the amount of light from the light source is controlled based on the numerical value. This has resulted in a disadvantage that the circuit configuration becomes complicated and maintenance of the device is time-consuming. Furthermore, since the change in magnification and the relationship between the detection value of the light receiving sensor and the exposure amount of the photoreceptor are not constant, it is very difficult to set accurate arithmetic processing.

〈発明の目的〉 この発明は上記不都合に鑑み、複写倍率を変化させても
受光センサの検出値と感光体の露光量の関係が変化しな
い光学的機構を使用することによって、複雑な演算処理
が不要な自動露光調整装置を提供することを目的とする
。<Object of the Invention> In view of the above-mentioned disadvantages, the present invention uses an optical mechanism in which the relationship between the detection value of the light receiving sensor and the exposure amount of the photoreceptor does not change even when the copying magnification is changed, thereby eliminating the need for complex arithmetic processing. The purpose is to provide an unnecessary automatic exposure adjustment device.

〈発明の構成〉 この発明は、受光センサを光源下方に近接させて設置し
、露光光路上にスリットを持つ遮光板を原稿面付近に配
設することを特徴とする。<Structure of the Invention> The present invention is characterized in that a light receiving sensor is installed close to the bottom of the light source, and a light shielding plate having a slit on the exposure optical path is placed near the surface of the document.

〈実施例〉 図はこの発明の実施例である自動露光調整装置を装備す
る可変倍率の複写機の要部構造図である。光源ｌから放
射される光は反射板２によって略原稿３上の図に垂直な
直線部分３ａ上に集光される。直線部分３ａで反射され
た光線ｌは反射鏡８．９．１０．１２を介し、また複写
レンズ１１で焦点調整をされて感光ドラム１３上で結像
しこの感光ドラムを露光する。前記原稿上の直線部分３
ａと最初の反射鏡８との間の光路上にはその光路上に５
ｍｍ〜１０ｍｍ程度のスリン）７ａを持つ遮蔽板７があ
る。反射板２の下方には受光センサ５が設置され前記反
射板２と受光センサ５の間には断面り字形の遮蔽板６が
取り付けられている。<Embodiment> The figure is a structural diagram of a main part of a variable magnification copying machine equipped with an automatic exposure adjustment device according to an embodiment of the present invention. The light emitted from the light source 1 is focused by the reflection plate 2 onto a straight line portion 3a on the original 3 substantially perpendicular to the drawing. The light beam l reflected by the straight line portion 3a passes through the reflecting mirrors 8, 9, 10, 12, and is focused by the copying lens 11, and forms an image on the photosensitive drum 13, thereby exposing the photosensitive drum. Straight line portion 3 on the original document
5 on the optical path between a and the first reflecting mirror 8.
There is a shielding plate 7 having a thickness of about 10 mm to 10 mm. A light receiving sensor 5 is installed below the reflecting plate 2, and a shielding plate 6 having an angular cross section is attached between the reflecting plate 2 and the light receiving sensor 5.

遮蔽板６は開口部６ａを有し、前記受光センサ５はこの
開口部６ａを介して前記原稿上の直線部分３ｂの反射光
を受光している。この原稿上の直線部分３ｂは前記原稿
上の直線部分３ａの走査方向に関して前方に位置し、そ
の間隔Ｘは図示しない制御回路が受光センサ５の検出値
を処理し光源１をフィードバック制御するためにかかる
時間の間後述する走査が進む距離に相当する。以上の構
成で光源１２反射２．受光センサ５．遮蔽板６．７及び
反射鏡８で構成される可動部Ａは図中に示す走査方向に
移動して原稿を走査する。また反射鏡９．１０で構成さ
れる稼働部Ｂは前記稼動部Ａの移動の１／２の速度で同
方向に移動する。感光ドラム１３は可動部Ａの移動速度
に対応する周速度で回転しドラム上に潜像を形成してゆ
く。The shielding plate 6 has an opening 6a, and the light receiving sensor 5 receives the reflected light from the straight portion 3b on the document through the opening 6a. The straight line portion 3b on the document is located in front of the straight line portion 3a on the document in the scanning direction, and the interval X is set so that a control circuit (not shown) processes the detection value of the light receiving sensor 5 and performs feedback control of the light source 1. This time period corresponds to the distance traveled by scanning, which will be described later. With the above configuration, the light source 12 reflection 2. Light receiving sensor 5. A movable portion A consisting of a shielding plate 6.7 and a reflecting mirror 8 moves in the scanning direction shown in the figure to scan the original. Further, the working section B, which is composed of the reflecting mirrors 9 and 10, moves in the same direction at half the speed of the movement of the moving section A. The photosensitive drum 13 rotates at a circumferential speed corresponding to the moving speed of the movable portion A, and forms a latent image on the drum.

ここで手動操作で複写倍率を変化させると、複写レンズ
１１の焦点距離が変化して感光ドラム１３上に結像する
像の大きさが変化する。この状態で複写を行なうと、前
記感光ドラム１３上に結像する像の露光量は複写倍率の
変化に伴って変化する。その露光量は変倍をβ（０〉β
）とすると前記スリット７ａを５ｍｍ〜１０ｍｍに設定
することによってｎ＝−β／（１−β）２で計算される
ことが知られている。従ってβ＝−０，６４７としても
光量の変化は５％程度である。実際の使用時における変
倍皐はβ−−０，７０７程度であるので実用上光量変化
を無視することができる。受光センサ５は光源下方に設
置されているため変倍時にも同一条件で原稿光量を測定
している。そのため変倍時にも複雑な演算処理なしに受
光センサ５の検出値で光源１の光量を制御することがで
きる。When the copying magnification is changed manually, the focal length of the copying lens 11 changes, and the size of the image formed on the photosensitive drum 13 changes. When copying is performed in this state, the exposure amount of the image formed on the photosensitive drum 13 changes as the copying magnification changes. The exposure amount is β(0>β)
), it is known that n=-β/(1-β)2 is calculated by setting the slit 7a to 5 mm to 10 mm. Therefore, even if β=-0,647, the change in light amount is about 5%. Since the magnification change during actual use is approximately β-0.707, changes in light amount can be ignored in practice. Since the light receiving sensor 5 is installed below the light source, it measures the light amount of the original under the same conditions even when changing the magnification. Therefore, even when changing the magnification, the amount of light from the light source 1 can be controlled using the detected value of the light receiving sensor 5 without complicated arithmetic processing.

〈発明の効果〉 光路上にスリットを設けることによって、複写倍率を変
化させても感光板の露光量がほぼ一定になるため、変倍
時でも受光センサの検出値の複雑な演算処理なしに光源
の光量を制御できるという利点が生じる。<Effects of the Invention> By providing a slit on the optical path, the exposure amount of the photosensitive plate remains almost constant even when the copying magnification changes, so even when changing the magnification, the light source can be used without complicated calculation processing of the detected value of the light receiving sensor. This has the advantage that the amount of light can be controlled.

【図面の簡単な説明】[Brief explanation of drawings]

図はこの発明の実施例である自動露光調整装置を装備す
る可変倍率の複写機の要部構造図である。 １−光源、２−反射板、５−受光センサ７−遮蔽板、７
ａ−スリット、１３−感光ドラム′出願人　シャープ株
式会社 代理人　弁理士　小森久夫The figure is a structural diagram of the main parts of a variable magnification copying machine equipped with an automatic exposure adjustment device according to an embodiment of the present invention. 1-light source, 2-reflection plate, 5-light receiving sensor 7-shielding plate, 7
a-slit, 13-photosensitive drum' Applicant: Sharp Co., Ltd. Agent Patent attorney: Hisao Komori

Claims (1)

【特許請求の範囲】[Claims] （１）複写倍率を連続的に変化できる複写機で、複写中
に受光センサによって走査部分の原稿濃度を検出しリア
ルタイムで光源の光量を制御する自動露光調整装置にお
いて、 前記受光センサを光源下方に接近させて設置し、露光光
路上にスリットを持つ遮蔽板を原稿面付近に配設するこ
とを特徴とする自動露光調整装置。(1) In a copying machine that can continuously change the copying magnification, in an automatic exposure adjustment device that detects the density of the scanned part of the document during copying using a light-receiving sensor and controls the amount of light from the light source in real time, the light-receiving sensor is moved below the light source. An automatic exposure adjustment device characterized in that a shielding plate is installed close to each other and has a slit on an exposure optical path near a document surface.
JP59103192A 1984-05-21 1984-05-21 Automatic exposure adjusting device Granted JPS60244942A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP59103192A JPS60244942A (en) 1984-05-21 1984-05-21 Automatic exposure adjusting device
US06/734,097 US4636063A (en) 1984-05-21 1985-05-15 Automatic exposure adjusting device
DE19853517915 DE3517915A1 (en) 1984-05-21 1985-05-18 AUTOMATIC EXPOSURE ADJUSTMENT DEVICE

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59103192A JPS60244942A (en) 1984-05-21 1984-05-21 Automatic exposure adjusting device

Publications (2)

Publication Number Publication Date
JPS60244942A true JPS60244942A (en) 1985-12-04
JPH0452932B2 JPH0452932B2 (en) 1992-08-25

Family

ID=14347649

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59103192A Granted JPS60244942A (en) 1984-05-21 1984-05-21 Automatic exposure adjusting device

Country Status (3)

Country Link
US (1) US4636063A (en)
JP (1) JPS60244942A (en)
DE (1) DE3517915A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6123142A (en) * 1984-07-12 1986-01-31 Ushio Inc Exposing device with exposure quantity sensor of copying machine
JPS6172228A (en) * 1984-09-18 1986-04-14 Ushio Inc Light quantity control method of light source lamp in copying machine

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6263944A (en) * 1985-09-13 1987-03-20 Minolta Camera Co Ltd Electrophotographic copying machine
JPS62105573A (en) * 1985-10-31 1987-05-16 Sharp Corp Original reader
GB2182781B (en) * 1985-11-13 1989-10-25 Ushio Electric Inc Exposure intensity detecting system for copying machine
US4699497A (en) * 1986-05-21 1987-10-13 Xerox Corporation Illumination lamp assembly for a document scan system
US4806775A (en) * 1987-01-14 1989-02-21 Ricoh Company, Ltd. Image reading system using an LED array
JPS63138540U (en) * 1987-03-03 1988-09-12
JPS646938A (en) * 1987-06-30 1989-01-11 Toshiba Corp Image forming device
JPH0827494B2 (en) * 1987-07-02 1996-03-21 ミノルタ株式会社 Copier
DE3918599C2 (en) * 1988-06-07 1994-01-27 Ricoh Kk Process for making sets of copies sorted by template size
JP2685816B2 (en) * 1988-06-30 1997-12-03 株式会社東芝 Light control device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5182630A (en) * 1975-01-16 1976-07-20 Minolta Camera Kk
JPS5489627A (en) * 1977-12-27 1979-07-16 Canon Inc Exposure regulator
JPS5768876A (en) * 1980-10-17 1982-04-27 Canon Inc Copying device
JPS58214142A (en) * 1982-06-07 1983-12-13 Toshiba Corp Picture density detector for picture producer

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2553665C2 (en) * 1975-11-28 1984-10-18 Agfa-Gevaert Ag, 5090 Leverkusen Field stop in a copier
EP0077988B1 (en) * 1981-10-23 1986-03-19 Kabushiki Kaisha Toshiba Image density detecting unit for image formation apparatus
JPS58158662A (en) * 1982-03-16 1983-09-20 Canon Inc Solid-black preventing device of electrophotographic copying machine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5182630A (en) * 1975-01-16 1976-07-20 Minolta Camera Kk
JPS5489627A (en) * 1977-12-27 1979-07-16 Canon Inc Exposure regulator
JPS5768876A (en) * 1980-10-17 1982-04-27 Canon Inc Copying device
JPS58214142A (en) * 1982-06-07 1983-12-13 Toshiba Corp Picture density detector for picture producer

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6123142A (en) * 1984-07-12 1986-01-31 Ushio Inc Exposing device with exposure quantity sensor of copying machine
JPS6172228A (en) * 1984-09-18 1986-04-14 Ushio Inc Light quantity control method of light source lamp in copying machine

Also Published As

Publication number Publication date
JPH0452932B2 (en) 1992-08-25
DE3517915C2 (en) 1987-10-29
US4636063A (en) 1987-01-13
DE3517915A1 (en) 1985-11-21

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